高铁水兑入比电炉炉盖用镁铝尖晶石浇注料的研制

Development of magnesium aluminate spinel castable for cover of EAF with high molten iron adding ratio

以粒度≤8 mm特级高铝矾土颗粒和烧结镁砂为骨料,SiO2微粉、α-Al2O3微粉、铝酸钙水泥作结合剂,分别制得镁铝尖晶石质浇注料和铝酸钙水泥结合高铝质浇注料。对试样分别进行烘干、1 350℃3 h和1 500℃3 h热处理并检测其体积密度、抗折强度、耐压强度、加热永久线变化、抗热震性和抗渣性。结果表明:与铝酸钙水泥结合高铝质浇注料相比,镁铝尖晶石质浇注料具有较高的烘干耐压强度,优良的抗渣性,但抗热震性较差。因此,在高铁水兑入比的电炉中,镁铝尖晶石质电炉盖表现出了更长的使用寿命。

Specimens of magnesium aluminate spinel castable and calcium aluminate cement bonded baux- ite based castable were prepared using special bauxite （particle size ≤8 mm） and sintered magnesia as aggregates,SiO2 micropowder,α-alumina micropowder and calcium aluminate cement as binders, drying, firing at 1 350 ℃ and 1500 ℃ for 3 h, respectively. The bulk density, modulus of rupture, cold crushing strength, permanent change in dimensions on heating, thermal shock resistance and slag resistance were determined. The result shows that compared with calcium aluminate cement bonded bauxite based castable,the magnesium aluminate spinel castable has higher cold crushing strength after drying, better slag resistance but worse thermal shock resistance. Magnesium aluminate spinel based lid of EAF with high molten iron adding ratio has longer service life.